There is an issue with v2018 Project Files (.vwxp), when someone by accident opens it in 2019, it without warning converts the .vwxp file to v2019 even all the following dialogs have been canceled. It doesn't save a copy of the new version it changes the original .vwxp file. In a result it looses all the other connections to local files on other machines; and uncommitted changes are lost. Plus the conversion brings in all the glitches.
There is no problem opening .vwx file as it pops up dialog box.